<html>
<head>
    <title>标题</title>
    <style type="text/css">
	div{
	 width:100px;
	 height:100px;
	 margin:100px;
	 background:red;
	}
	#sss {background:green;}
	.zzz {background:blue;}
    </style>
</head>
  <body>
  	<div class="zzz"></div>
  	<div id="sss"></div>
  	<div class="zzz"></div>
  </body>
</html>
